Studying the synthesis of natural products provides rich opportunities for identifying new directions in chemistry and biology. The overarching goal of our research program is to study the chemical synthesis of small molecules of medicinal relevance and to advance chemical technology for the next-generation of drug synthesis. Through this project, we will better understand how nature performs cycloaddition-type dimerization reactions to produce higher order pyrrole-imidazole alkaloids. We will test the biosynthetic hypotheses and develop biomimetic synthetic approaches to these natural products. Inspired by the oxidative metalloenzymes, we will further develop new catalyst systems for C-H and olefin oxidation. We will also study how cyclic dinucleotides mediate innate immune response. Our research will have direct impacts on the discovery and manufacturing of small-molecule drugs.